1. File and Image Preview System Enhancement
   - Implemented comprehensive file and image preview functionality before sending to operator
   - Added temporary file handling with new `tmp` field in `lh_chat_file` table
   - Enhanced widget React components to support file preview with better user experience
   - File attachments are now rendered at the top of messages for better visibility
   - Improved file upload workflow with progress indicators and preview capabilities
   - This enhancement prepares the foundation for future OpenAI Responses API for images implementation

2. Widget and Chat Interface Improvements
   - Enhanced attachment rendering system with dedicated top-level templates
   - Improved AI-generated content checks and validation
   - Better file uploader component with enhanced preview functionality
   - Optimized widget React components for better performance and user experience
   - Enhanced chat file handling with improved meta message rendering

3. Department and Chat Management Enhancements
   - Added support for using department alias when provided in chat widget and status checks
   - Improved department handling logic for better chat routing
   - Enhanced chat widget functionality with streamlined department selection

4. Export and Data Handling Improvements
   - Fixed JSON export formatting with proper UTF-8 charset headers for Unicode support and pretty printing (#2283)
   - Enhanced bot export functionality with correct content-type headers
   - Improved REST API export with proper encoding
   - Better theme export handling with Unicode support

5. File Configuration and Management
   - Added new file configuration options for better file handling control
   - Enhanced file upload settings with improved validation and processing
   - Better integration between file upload API and widget components
   - Improved file metadata handling and storage

6. Technical Infrastructure Improvements
   - Updated database structure with new temporary file handling capabilities
   - Enhanced widget REST API endpoints for better file and chat management
   - Improved translation support and internationalization

7. User Experience Enhancements
   - Streamlined file attachment workflow with instant preview
   - Better visual feedback for file operations
   - Enhanced message rendering with improved attachment display
   - Optimized loading and rendering performance for file-heavy conversations

For update just follow standard update procedure. For manual update it's update_337.sql

## What's Changed

**Full Changelog**: https://github.com/LiveHelperChat/livehelperchat/compare/4.68v...4.69v